All year conditioning apparatus



Jan, 31, 1950 NEWTON 2,495,861-

ALL YEAR comrrmumc APPARATUS Filed April 18, 1945 3 Sheets-'-Sheet 1 Jan. 31, 1950 I A. a. NEWTON 2,495,861

ALL YEAR CONDITIONING APPARATUS 3 Sheets-Sheet 3 197T 0/?IVE Y quirements may differ.

Patented Jan. 31, 1950 2,495,861 7 ALL YEAR CONDITIONING ArrAItA'rI'Is Alwin B. Newton, Dayton, Ohio, assignor to Minneapolis-Honeywell Regulator Company, Minneapolis, Minn., a corporation of Delaware Application April 18, 1945, Serial No. 588,952

24 Claims. (Cl. 257-3) This invention relates to an improvedall year space conditioning apparatus and has for one of its principal objects the provision of means for the delivery and control of the conditioning medium to a plurality of spaces or zones responsive to the individual requirements thereof.

The improved apparatus includes an individual control means for each space or zone to be conditioned. The control means may take the form of the device shown and described in my copending application, Serial No. 580,427. filed March 1, 1945. However, various modified forms of control means may be employed without departing from the scope or spirit of the present invention.

A purpose of the apparatus of this invention is to provide an eflicient and completely automatic means for the all year conditioning of buildings or the like which are divided into a plurality of spaces, zones, or rooms, in which conditioning re- During portions of the year such conditioning may be carried on by either the heating or cooling portions of the device. However, during the change-over period spring and fall, it is necessary and desirable to provide intermittent operation and control by both heating and cooling portions of the apparatus. For instance, it may be that during the change-over period, or even at other times, one portion of the building may require cooling and another portion thereof may call for heat. Under such conditions, the improved device of this invention functions to deliver the required c'onditioning medium through a single duct work, or passage means as will hereinafter be more fully described.

Another object of advantage and importance of the improved apparatus resides in the provision of means for treating or preparing a conditioning medium to meet requirements of opposite extremes and of delivering the medium so prepared through a single passage means to a plurality of spaces or zones in which different conditioning is required. The differing requirements may range from a mere difference in volume to a difference in the temperature of the conditioning medium.

Another object of advantage and importance resides in the provision of means for having continuously available a conditioning medium, the delivery of which is governed by individual control means of the various zones. With the improved apparatus of this invention the zone requirements are met although one zone may call for capacity conditioning and another zone may call for no conditioning whatever.

Another object of advantage and importance is the provision of means for maintaining the pressure of the conditioned medium of the apparatus within a predetermined range, regardless of the action of the individual control means.

An additional object of importance is the provision of means for automatically limiting the extent of conditioning of the medium preparatory to delivery to the zones, and of automatically reducing the limit of conditioning in accordance with an increase in the pressure of the conditioned medium within the apparatus.

A further object of importance and advantage resides in the provision of means for utilizing both heating and cooling conditioning units in the apparatus and for rendering one of the units ineffective during the time the other unit is treating the conditioning medium.

Additional objects of advantage and importance will become apparent as the following description progresses, reference being had to the accompanying drawings whereim Figure 1 represents a sectional elevation of a portion of a building in which a conditioning unit, which embodies the invention, is positioned. The apparatus is diagrammatically shown partly in section and having parts thereof broken away to more clearly illustrate the device.

Figure 1a is an elevational view of the operating mechanism of an outlet control.

Figure 2 is a wiring diagram of a circuit used with the apparatus shown in Figure 1.

Figure 3 illustrates a slightly modified form of the invention.

Figure 4 is a wiring diagram of a circuit use with the apparatus shown in Figure 3.

Figure 5 is a slightly enlarged view of the closure control assembly portion of the structure shown in Figure 3.

Referring now to Figure 1, the conditioning apparatus of this invention comprises a heater which may be in the form of a warm air furnace generally designated by the reference numeral ID, a cooling unit II, and a circulating fan l2. The warm air furnace I0 is provided with a bonnet l3, and a heat exchanger ll indicated by dotted line. A fuel supply line is shown in the form of a pipe I5 and flow therethrough is controlled by means of a valve I6.

Extending from the bonnet 13 to a space, or plurality of spaces, to be conditioned is a duct IT. The duct I1 is shown extending beneath the modem 3 floor it of a building in which the apparatus is positioned and has branches thereon indicated by the reference numeral 20 extending upwardly from a continuation ll thereof. through the floor II and walls 2| to deliver conditioned air into the adjacent spaces. Each branch 2. is provided with a controlling outlet 22 which is disposed substantially flush with the wall to which it is attached. The outlets are provided with individual control means, the bulb portions of which are adapted to be positioned in a housing generally indicated by the reference numeral 224 and manual adjusting knobs 28. The individual control means for the outlets 22 are more fully described in my copending application Serial No. 580,427, but for the sake of clarity are illustrated and briefly described herein. Each individual unit comprises a bulb and bellows joined by a tube which functions to position a closure associated with the outlet. The unit for controlling the outlet during heating cycles is indicated generally by the reference character H and the unit for controlling the outlet during cooling cycles is indicated by the reference C. The bellows portions of the units are preferably mounted in a frame, in substantially the manner shown in Figure 1a, which is adapted to be positioned in the flow of the conditioning medium and upstream of the outlet. The bulb portions of the units are adapted to be positioned in the space to be conditioned and closely adjacent the controlled outlet. Provision is made for aspirating space air over the bulbs during operation of the apparatus as is more fully set forth and disclosed in my above mentioned copending application. Each bellows member operably engages an operating arm which in turn is connected, preferably by a chain A, to an associated outlet. Adjustable spring means H3 and CI for biasing the bellows members toward collapsed position are connected, one to an operating lever HI and the other to an operating lever CI. The bellows of the H unit is provided with an internal stop H2, shown in dotted lines in Figure 1a, to limit contraction of the H bellows and the bellows of the C unit is provided with an external stop C2, formed by a turned portion of the frame, to limit expansion of the C bellows. The stop H2 functions as an anvil or support for a. fulcrum when the cooling unit is in control and the stop C2 functions as a support for a fulcrum when the H unit is in control of the outlet as hereinafter described.

The H unit is charged with a small quantity of a volatile fluid which at a given temperature assumes a saturated vapor state and produces a predetermined pressure. This unit is commonly known as a limited fill or a fade out unit and is adapted to normally operate under conditions wherein the bellows portion of the unit is always warmer than the bulb portion thereof. Should any portion of the H unit cool below the given temperature or fade out point which may be approximately the desired room temperature at which the control knob is set, the vapor therein condenses in ratio to such cooling and pressure within the unit is reduced. Now when the apparatus is on a cooling cycle and the bellows is subjected to a flow of cooled air, the charge therein is cooled and assumes a liquid states thus reducing the pressure in the unit. When the pressure in the unit falls below the tension value at which the spring H3 is set, the spring prevails to collapse the bellows onto the internal stop I 4 H2. when the apparatus is heating cycle and the H bellows is subjected to heated air any condensate in the bellows h vaporized. Under these conditions, the bulb is the coolest portion of the unit and any'liqulilcation of the charge in the unit takes place in the bulb. Consequently, pressure inthe unit is responsive to and in accordance with the temperature of the bulb. This pressure within the unit expands the bellows and controls the positioning of the closure member. 7

The C unit is charged with a volatile fluid which in its liquid state completely fills the bellows, tube and a portion of the bulb. This unit is commonly known as a high temperature 1111 unit and is adapted to normally operate under conditions wherein the bellows portion thereof is always cooler than the bulb portion of the unit. Accordingly, under normal operating conditions, this unit is controlled by the temperature of the bulb or that portion of the bulb thermally effecting the liquid surface of the 1111. When the apparatus is on a heating cycle an abnormal condition is created for this unit and the bellows becomes warmer than the bulb. Accordingly, liquid within the unit is expanded and vaporized increasing the pressure therein to drive the bellows against the external stop C2.

Accordingly, it will be apparent that during a heating cycle a normal operating condition exists for the H unit and an abnormal operating condition exists for the C unit. As a result of this condition the expansion and vaporization of fill in the C unit pressure therein drives the bellows against the stop C2 to provide a fulcrum upon which the operating arm 0 may rotate. During-the heating cycle all condensation in the H bellows is vaporized and control operation of that unit is in accordance with the temperature of the bulb portion thereof. During a cooling cycle a normal operating condition exists for the C unit and an abnormal operating condition exists for the H unit. As a result of this condition the charge in the fade out fill unit is condensed in the cooled bellows portion thereof which reduces pressure in the unit and permits the collapse of the bellows onto the internal stop H2 to provide a. fulcrum for the operating arm 0. During the cooling cycle, the charge in the bellows portion of the C unit is condensed and contracted reducing pressure in the unit and permitting the bellows to contract from the external stop C2. During the cooling cycle, control of operation of the C unit is in accordance with and responsive to the temperature of the portion of the bulb adjacent the surface of the charge in the unit.

Thus it will be apparent that control of the outlets is obtained by taking advantage of and utilizing reaction characteristics of temperature control units operating under normal and abnorm'al conditions and of so applying the reactions of these units that one part thereof, the bellows, functions to determine which of the two will prevail under certain conditions and another part thereof, the bulb, functions to determine to what extent the controlling unit will operate.

The cooling unit II is preferably positioned closely adjacent the warm air furnace l0 and may comprise a substantially rectangular body having a cooling coil 23 positioned therein. A coolant may be supplied to the coil 23 through a supply pipe 24 and flow therethrough may be controlled by valve 26. Extending from the upper operatingona portion of the cooling unit II and connected to the duct 11 is a duct 21. The ducts I1 and 21 are joined to the continuation I! by means of a connecting member 29, as is best shown in Figure 1.

The circulating fan I! is preferably interposed between the warm air furnace Hi and the cooling unit II as shown in the drawing. The fan I2 is provided with a substantially T-shaped outlet duct 28 and has a portion 28a thereof extending into the warm air furnace l and a similar portion 28b extending into the cooling unit Positioned within the duct 28 is a damper 38 operable to two positions. In one position, the damper 38 blocks oil the passage to the cooling unit II and permits air to flow into the warming furnace III. In the other position, as shown in Fig! ure 1, the damper 38 closes off the passage to the warm air furnace and permits air to flow from the circulating fan to the cooling unit. The damper 38 is moved to its two positions by means of a motor 3|. The motor 3| is commonly known as a two-position motor adapted to operate a driving member in half revolution movements. Upon completing each half revolution movement, the motor is automatically deenergized and remains inactive until reenergized to make another half revolution movement. The motor 3| is preferably positioned on the duct 28 and is connected to the damper by means of a linkage 32.

Positioned at the junction of the ducts l1 and 21 is a damper 33. The damper 33 is arranged tobe operated to two positions by a motor 34 connected thereto 'by linkage means 36. The motor 34 is a two-position motor similar to the motor 3|. The damper 33 is operable to a position, as shown, in which the conditioned air or medium is permitted to flow from the cooling unit through the duct 21 and the outlets 22 and is prevented from flowing from the warm air furnace through the duct l1. In the dotted position of the damper, conditioned air is permitted to flow from the warm air furnace through the duct H to the outlets 22 and is prevented from flowing from the cooling unit to the outlets 22. Movement of the dampers 38 and 33 and the motors 3| and 34 is in unison.

Leading from one or more of the spaces to be conditioned to a cabinet 31 which houses the circulating fan I2 is a return duct 38. Accordingly, return air from the space or spaces being conditioned is directed downwardly, as indicated by the arrows, through the return duct 38 and into the fan cabinet 31. Positioned in the cabinet 31 intermediate the lower end of the return duct 38 and the circulating fan I2 is an air filter 39.

Mounted on a side wall of the warm air furnace I8 and forming a closure for a passageway from the interior of the furnace to the interior of the circulating fan cabinet 31 is a hinged damper 40. The damper 40 is biasedto closed position and normally functions to prevent the flow of air from the furnace into the cabinet. The damper 40 is biased to closed position by means of an adjustable biasing spring 4|. Secured to the hinge portion of the damper 40 and rotatable in respect to the stationary portion of the hinge and the wall of the cabinet 31 is a hinge pin 44. One end of the pin 44 extends outwardly from a wall of the cabinet and has an operating lever 50 attached to the projecting portion. Operably connected-to the lever 50 by linkage means 42 is a temperature control switch 43. The temperature control switch 43 is adjustable to operate in response to variations in temperature throughout a. limited range and movement of the damper in opening or closing directions operates to adjust or reset the temperature control switch downwardly or upwardly, respectively, in relation to such damper movement. The temperature control switch 43 is electrically connected to the fuel supply valve IS in a manner and for a purpose to be hereinafter set forth.

Positioned on the wall of the cooling unit and forming a. closure for a passage extending from the interior thereof to the interior of the circulating fan cabinet 31 is a hinged damper 45. The hinged damper 45 is biased to closed position by means of an adjustable biasing spring 46. Fixed to the damper 45 and journalled to a wall of the cabinet 31 is a hinge pin 44. One end of the pin 44 extends outwardly from the wall of the cabinet 31 and has an operating lever 50 attached thereto. The lever 50 is Operably connected to a temperature control switch 41 by linkage means 48. Movement, of the damper45 in opening or closing direction also moves the temperature control switch to a higher or lower setting, respectively. It is to be noted that dampers 40 and 45 are pressure actuated and that movement of the damper 40 in an opening direction causes the resetting of the temperature control switch 43 to a lower setting and that movement of the damper 45 in an opening direction causes a resetting of the temperature control switch 41 to a higher temperature setting.

Located at an intermediate point between the damper operated motors 3| and 34 and an outdoor thermostat 49 is a timer mechanism 52. The timer which is adapted to intermittently open and close an electric circuit is electrically connected to the outdoor thermostat and to the motors 3| and 34 by means of a circuit hereafter described.

Positioned in a suitable location and lectricab ly connected to the control element of the apparatus is a night shut-down switch 63. The switch 63 functions to control the operation of the entire system. When the switch is open, electrically operated members, including the fan, are deenergized and the valves l6 and 26 are closed.

The outdoor thermostat 49 may be set to operate the timer within a given range; for the purpose of illustration, say between 50 and 65 degrees. At all temperatures above the high limits of the timer setting, the outdoor thermostat 49 establishes a first circuit which causes the dampers 30 and 33 to move to the positions at which they are shown in Figures 1 and 2, which movement closes the fuel supply valve l6, and opens the coolant supply valve 26 to cause the apparatus to function. At all temperatures below the low limits of the timer actuating range,

the outdoor thermostat 39 establishes a second circuit which causes the dampers 3|] and 33 to move to the left extreme of their travel, which movement closes the coolant supply valve 23, and opens the fuel supply valve I6, causing the heating side of the apparatus to function. At all temperatures within the range, the outdoor thermostat establishes a third circuit which causes the timer to intermittently operate the dampers 38 and 33 and the valves l6 and 26 to cause one side of the apparatus and then the other to alternately function.

The first circuit which actuates the cooling side of the apparatus is initiated when the outdoor temperature rises and moves the bimetal element in the outdoor thermostat to the position in which 1 it is shown in Figure 2. This movement brings a contact arm 53 into engagement with a contact member 54 to establish a circuit which may be traced as follows: from a source of supply through conductor 55 to closed night shut-down switch 53,

conductors 55 and 51, contact arm 53, contact 54, conductor 58, and parallel conductors 59 and 58, previously closed switches 58a and 58a, motors 34 and 3|, thence returning by conductors GI, 54,

and 55 to the source of supply. Damper motors.

3| and 34 were thereby moved to the position shown in which switches 58a and 88a are opened and the damper motors are stationary. A cooling valve operating circuit established by movement of damper 33 to the cooling position shown is as follows: from conductor 58, to conductor 55, switch 62, conductor 51, temperature control switch 41, conductor 88, valve 25, conductor 58, and conductor 65 to the source of supply.

The second circuit which actuates the heating side of the apparatus is initiated by movement of the bimetal element to the left to engage contact I upon outdoor temperature fall. This circuit may be traced as follows: from a source of supply through conductor 55, night shut-down switch 53, conductors 56 and 51, contact 53, contact l0, conductor 1|, parallel conductors l2 and 13, switches 12a and 13a, motors 34 and 3|, conductors 5|, 54, and G5 to source of supply. This moves the damper motors through a half revolution to open switches 12a and 13a and close switches 58a and 60a. Also movement of damper 33 to its opposite position opens the cooling valve circuit and closes a heating valve circuit as follows: from conductor 58, to conductor 66, switch 82. conductor 14, temperature control switch 43, conductor 15, valve I6, conductors 15 and 85 to source of supply.

The third circuit which actuates the timer when the outdoor temperature is intermediate may be traced as follows: from a source of supply through conductor 55, night shut-down switch 83, conductors 56 and 51, contact arms 53, contact 'll, conductor I8, conductor 18, timer 52, conductors 88 and 55 to source of supply. Operation of the timer in alternately closing and openings contacts 8| and 82, and BI and 83, alternately energizes circuit as follows: from conductor I8, to conductor 84, arm 85, movable contact 8|, contact 82, conductor 86, and parallel conductors 58 and 50 to switches 59a and 60a, to motors 34 and 3|, conductors 64 and 6|, conductor 55 to source of supply. And the alternate circuit is as follows: from conductor 18 to conductor 84, conductor 85, contacts 8| and 83, conductor 81, parallel conductors l2 and 13, switches 12a and 13a, motors 34 and 3|, conductors 64 and 5|, and conductor 85 to source of supply.

It is to be noted that the circulating fan I2 is connected directly across the line through the night shut-down switch 63 by conductors 55, 88, and 89. Accordingly, as long as contacts of the night shut-down switch 63 are closed, the circulating fan i2 is in continuous operation.

Operation With the parts in the position in which they are shown in Figure 1, it being understood that the outlet controls and outdoor thermostat 48 have been set as desired, operation of the apparatus shown in Figure 1 is as follows: It is to be noted that the bimetallic element 53 of the outdoor thermostat 48 is in engagement with contact 54 and as the result of the establishment of the first circuit, the motors 3| and 34 have moved the dampers to their extreme right-hand position closing of! the heating side of the apparatus and permitting the delivery of air from the continuously operating circulating fan i2 through the cooling side of the apparatus in the direction indicated by the arrows and outwardly through the outlets 22. The movement oi the damper 33 has operated the switch 82 to energize and open cooling valve 25 and deenergize and close heating valve l5. Assume now that the temperature of one of the rooms or spaces being conditioned reaches a point at which the control of its outlet 22 is satisfied. This outlet thereupon closes, which action results in a slight increase in the pressure of the conditioned air within the duct 21 and the cooling unit I I. Dependent upon the adjustment of the biasing spring 41, this increased pressure may be sufficient to cause opening movement of the damper 45. If so, the moving damper relieves pressure within the system and at the same time resets the temperature switch 41 to a higher limit. Now assume that the control element of a second outlet 22 becomes satisfied and closes another outlet. Obviously, pressure within the system is again slightly increased resulting in further opening of therelief damper 45 and the resetting of the temperature control switch 41 to an even higher limit. Assume now that the control elements of all of the outlets 22 are satisfied, and that the outlets are closed. As a result of closing all of the outlets, the pressure in the discharge side (that portion between the circulating fan and the discharge ports, of the unit), would be at its peak and pressure within the inlet side, (that portion between the circulating fan and the inlet of the return duct) would be at a low level. The unbalance pressure on the opposed sides of damper 45 would cause that member to move to an equalizing position in which flow from the cooling cabinet would be by-passed through the passageway controlled by the damper 45 and into the fan chamber to be recirculated. This condition would continue as long as the outlets remain closed and the night shut-down switch remains unmoved. Upon the opening of any of the outlet closures, pressure within the system would be relieved somewhat and the damper 45 under the force of gravity and the biasing spring 48 would move toward closed position.

Assume now that the bimetallic member 53 of the outdoor thermostat 48 in response to a lowering temperature moved into engagement with the contact 18. Such a movement of the bimetallic member would energize the second circuit which would result in operation of the motors 34 and 3| to move dampers 33 and 38 respectively, into their extreme left-hand positions. The movement of damper 33 would cause operation of the switch 52 to deenergize cooling valve 28 which thereupon would close, and to energize fuel valve i8 causing it, to open. The apparatus is now in position to deliver heated air into the rooms or spaces as required. If under these conditions the controls 22a of the outlet 22 are unsatisfied and the outlets are in full open position the relief damper 45 is closed and the temperature control switch 43 is set to a high position. As the control elements 22a become satisfied and close the outlets, pressure within the discharge side of the heating unit increases and causes opening of the relief damper 48 in precisely the same manner as previously described in relation to the cooling side. Accordingly, conditioned air is available at the discharge ends of the ducts as long as the bimetallic member of the outdoor thermostat, and the night shut-down switch, remain unmoved.

. Now assume that the bimetallic member 58 of the outdoor thermostat 49 moves to its intermediate position to engage the contact member 11. As a result of such movement a third circuit is completed which promptly energizes and starts the timer 52. The operation of the timer causes the contact member 8| to be moved alternately into engagement with contact member 82 and contact member 83. If when the contact member 8| engages the contact member 82 as shown in Figure 2, and switches 59a and 88 are in the position shown, no new operative movement results. Upon the continuation of the timer operation the contacts 8| and 82 are separated and the' contact 8| is moved into engagement with the contact 83. This results in the energization of motors 34 and 3| through switches 12a and 13a and the resulting operation of the motors moves the dampers 33 and 38 to their extreme left-hand positions to initiate a heating cycle. During the heating cycle, the coolant valve 26 is deenergized and inactive and the fuel valve I6 is active. During this heating cycle the outlets 22 function under the control of their heating thermostats and the damper 48 regulates the pressure within the system and also functions to reset the temperature control switch in accordance with the pressure within the apparatus. The continuing operation of the timer causes, at predetermined times, the separation of contacts 8| and 83 and the reengagement of contacts 8| and 82. The closing of contacts 8| and 82 results in the movement of the dampers 38 and 33 to the position in which they are shown in Figure 1 and thus initiate another cooling cycle. The periodicity of the cycles and the length of their duration may be varied throughout a wide range.

From the foregoing it will be apparent that as long as the bimetal member of the outdoor thermostat maintains its contact with the intermediate contact 11, the timer 52 will be energized and the improved apparatus will alternately operate on hot and cold cycles. During the time the bimetallic element of the outdoor thermostat is in engagement with the contact member 54, the apparatus will function to deliver air through the cooling side only and during that portion of the time when the bimetallic element is in enga ement with the contact member 18, the device will operate to deliver air throu h the heatin side only. ,Accordingly, there is herein provided a fully automatic all-year conditioning unit which is adapted to operate efficiently throughout summer months. when cooling air is reouired, winter months. when heating is recmired. and the changeover period during spring and fall when both heating and coolin is reduired'to deliver a conditioning medium to zones or rooms in accordance with the requirement of each particular zone or room. Furthermore, provision is made in the improved device for maintaining a substantially constant pressure therein regardless of the opening or closing of the control outlets and for varying the temperature of the heated or cooled air delivered to the outlets.

Modification In the modified embodiment of the invention as shown in Figures 3, 4, and 5. certain of the main elements are given the same reference numerals as are applied to similar parts of the preferred 10 embodiments shown in Figure 1. The modified structure comprises a warm air furnace generally indicated by the reference numeral l8, through which air may be driven by a continuously driven circulating fan |2. As in the preferred embodiment of the invention air circulated through the warm air furnace I8 is conditioned in its passage therethrough and may be delivered to a plurality of spaces or rooms through duct work l1 and I9 and branches thereof extending upwardly through the floor I8 oi the spaces or rooms to be conditioned. As in the preferred embodiment the branches 28 are preferably positioned in the walls 2| and each is adapted to be provided with an individual outlet control 22. The flow of fuel through the supply pipe l5 to the furnace I8 is controlled by an electrically operated valve IS. A return duct 38 extending from one or more of the rooms is connected to a cabinet 31 which houses the circulating fan |2, and a suitable filtering device 39 is disposed in the cabinet 31 intermediate the circulating fan l2 and the return duct 38.

Mounted on a wall of the warm air furnace I8 and providing a closure for a passage between the interior of the furnace and the interior of the circulating fan cabinet 31 is a hinged damper 98. The damper 98 is normally held in closed position by means of an adjustable biasing spring 9|. It is to be noted that the damper 98 differs slightly in construction and operation from the damper shown in the preferred embodiment as illustrated in Figure 1. However, it is also to be noted that the damper 98 of the modified embodiment may be employed on the preferred structure, or the damper 48 shown in the preferred structure may be employed on the modified form of the invention. The damper 98 is provided with a peripheral flange 9| which is turned at right angles to the body of the damper to form a substantially cup-shaped structure. When the damper 98 is in closed position, the flange 9| is adapted to overlap a projecting flanged portion of the passage between the interior of the furnace and the interior of the fan cabinet. As previously stated, the damper 98 is operably secured in position by means of a hinge 92 and a part of the pin receiving portion of the hinge is slotted, as indicated by the reference numeral 93, to permit horizontal movement of the damper 98 in respect to the wall to which the damper is secured. This horizontal or lateral movement of the damper 98 precedes and follows the opening and closing movements. respectively, of that member for a purpose hereinafter set forth.

Fixed to the hinged portion of the damper and rotatable in respect to the stationary portion of the hinge and the wall of the furnace, to which the hinge is attached, is a hinged pin 95. One

50 end of the hinged pin 95 extends outwardly throu h a wall of the fan cabinet 31 and has an operating member 96 operably attached thereto as is best shown in Figure 5.

Positioned on the furnace l8 and operably ioined. to the operating lever 96 by a connecting link 91 is an adiustable temperature control switch 98. An adiustable biasing spring 99 positioned on the connecting link 91 urges the relief member 98 toward closed position. This biasing sprin 99 in addition to urging the closure toward closed osition also functions to urge the adjustahle tem erature. control switch toward its high limit position. The relief damper is moved to the left'and opened by pressure within the outlet portion of the system and is moved to the right l1 and closed by gravity and the biasing spring 00. Movement of the damper operates the lever 00 and through the connecting link 01 resets the temperature control switch 00 which in turn controls the fuel supply valve II.

Located remotely of the conditioning unit, pref erably in one of the rooms or spaces to be conditioned, is a night shut-down switch I00. The night shut-down switch is electrically connected to the fan I2 and also through the temperature control switch 90 to the valve I6 for controlling the operation of that member. A manually operated switch I0l may also be provided for controlling the operation of the device.

Electrical energy for operating the fan and valve is supplied through the following circuits: from a source of supply through conductor I02, switch I0 I, conductor I00, night shut-down switch I00, conductor I04, terminal I05, conductor I00, circulating fan l2, conductor I01, terminal I00, and return by conductor I00 to the source of supply. A parallel circuit is also provided from terminal I through conductor H0, temperature control switch 90, conductor II I, supply valve I6, conductor H2, to terminal I08. The parallel circuit provides means whereby the circulating fan and the supply valve may be operated independently of each other, yet both are under the control of the night shut-down and manually operated switches I00 and IN. respectively.

Operation With the parts of the apparatus in the position in which they are shown in Figures 3, 4, and 5 of the drawing, the manually operated switch IN is opened, the contacts of night shut-down switch III are closed, the contacts of the temperature control or limit switch 98 are closed, the relief damper 00 is also closed, and the apparatus is at rest. Assume now that the outlets are in open position and the manually operated switch III is moved to closed position. The completed circuit energizes the circulating fan motor and the valve 60 causing the operation of both. With the circulating fan I! in operation, air is delivered through the duct 20. to the furnace l0 where because the furnace is in operation, the air is conditioned by heating as it passes therethrough on its way to the outlet 20. Inasmuch as the outlets are open, the conditioned air is delivered therethrough' into the rooms. So long as the control elements of the outlet 22 remain unsatisfied, the delivery of conditioned air into the rooms is continuous and its temperature is controlled by limit switch 90.

However, assume now that the control element of one outlet becomes satisfied and causes the outlet under its control to close. As a result of the closing of a portion of the outlet area of the apparatus, the pressure in the outlet portion, the part between the fan and outlet, of the apparatus increases slightly. This increase in pressure overcomes the biasing spring 99 and forces the relief damper 00 laterally to the left until stopped by the engagement of the hinge pin 95 with the left end of the slot 93. This movement of the damper permits leakage from the high pressure side to be by-passed into the inlet portion, the part between the circulating fan and the inlet of the return duct, thereof. This lateral movement of the damper is insufficient to equalize the pressure between the inlet and the outlet sides of the apparatus so the biasing spring remains slightly compressed and the damper I9 is maintained in its extended position. This movement of the dam er, which has little if any effect on the pressure within the system, causes the movement of the operating lever 06 to the left and with it movement of the connecting link 04 to the left to cause resetting of the temperature limit switch 00 to maintain a lower temperature in the furnace. Thus upon a very slight increase in pressure on ,the outlet side of the apparatus, the setting of the temperature control switch is altered, so as to reduce the effective temperature of the heat transfer element I4 within the furnace II. This movement is anticipatory of further shut-down or closing of the outlets and tends to prevent the building up of excess heat within the furnace II.

Now assume that the controls of a second outlet become satisfied and cause the closing of the second outlet. The decreased outlet capacity now acts to further increase the pressure within the outlet side of the apparatus. As a result pressure exerted against the relief damper 90 causes that member to swing outwardly upon its hinge to substantially the position in which it is shown in dotted lines in Figure 5. As a result of the opening of the damper 90 air is by-passed from the furnace into the fan chamber as indicated by the dotted arrow, to compensate for the closing of the outlet. The relief damper will adJust itself to a position in which the flow of air from the furnace into the fan cabinet will substantially equalize the pressure therein. Concurrently with the movement of the damper 00 to open position, the operating lever 98 functions to move the connecting link 94 further to the left to cause the temperature control switch to be reset to a still lower limit. The closing of other outlets in the system operates to cause the damper to open still further, and also causes the temperature control switch to be reset to a still lower limit. It will be apparent that as the outlets close the relief damper 90 is opened to admit air into the fan chamber 31. Consequently the passage of air from the room through the return duct 30 and into the fan chamber 31 is curtailed.

It will also be apparent that the circulating fan I2 may be operated in summer months or at other times when the hot air furnace is shut down, to circulate air over the cool furnace and deliver it to rooms or spaces for cooling purposes. In such a case the outlet controls function in substantially the same manner as they do during a cooling cycle of the preferred embodiment as herelnbefore described. It will also be apparent from the foregoing that herein is provided a conditioning apparatus adapted to deliver a conditioning medium in response to the requirement of the particular zone or space in which an outlet of the device is located regardless of the condition or requirements in spaces or zones adjoining or adjacent thereto. Moreover the improved apparatus of this invention operates at a substantially constant pressure regardless of the number of outlets in the system that are closed or open.

It will be apparent to those skilled in the art to which the improved apparatus of this invention pertains that numerous changes on construction and design may be made without departing from the spirit or scope of the invention. Accordingly, the patent granted hereon is not to be limited to the precise embodiments here disclosed or in any other manner except as may be necessitated by the terminology of the appended claims when given the range of equivalents to which they may be entitled.

I claim as my invention:

1. In a space conditioning apparatus comprising in combination a conditioning element, means for causing a medium to flow thereover and be conditioned, means having a plurality of outlets for conveying said conditioned medium under pressure from said conditioning element, flow control means responsive to space temperature and the temperature of said medium for control-, ling each of said outlets, means for preventing a substantial increase in the pressure in said conveying means as the discharge of the conditioned medium from said plurality of outlets is varied, and means responsive to the pressure of the conditioned medium in the apparatus for controlling the temperature of the conditioning element.

2. In a conditioning apparatus for servicing a plurality of rooms and comprising, a conditioning element, forced draft means for circulating a conditioning medium between said element and said rooms. said forced draft means including duct work having an outlet in each of said serviced rooms, individual control means associated with each of said outlets, said control means being responsive to the temperature of the conditioning medium and the temperature of the room being conditioned, and means for preventing a substantial increase of pressure in the apparatus while said forced draft means are in operation and said outlets are closed.

3. In a conditioning apparatus. a duct having an inlet and a plurality of outlet terminals, temperature responsive closure means for controlling flow of a conditioning medium from said outlet terminals, a circulator positioned in said duct intermediate the terminals thereof and operable to force a conditioning medium under pressure through said duct, conditioning means positioned in said duct intermediate said circulator and said outlet terminals and operable to condition a medium as it is passed through said duct, limit control means positioned for said conditioning means, and pressure responsive relief means operable to control pressure within said duct, said relief means also being operable to reset said limit control in accordance with the pressure within said duct.

4. In a conditioning apparatus, duct means having flow control means associated therewith, means for circulating a conditioning medium in said duct means, means for thermally conditioning a medium passing through said duct means, said conditioning means comprising means for raising or lowering the temperature of said conditioning medium to a predetermined value. means for causing the flow of the conditioning medium to be conditioned alternately by said temperature raising and lowering means, and means responsive to the pressure of the conditioned medium within said duct means for controlling the temperature of said conditioning means.

5. In a space conditioning system, conditioning means, a circulating element connected to said conditioning means and having supply and return duct work extending to the space to be conditioned, temperature actuated control means for controlling the discharge from said supply du"t work, said conditioning means and said duct work being disposed to alter the temperature of a conditioning medium as it is circulated therethrough, and means for controlling the alteration of said temperature in accordance with the pressure differential between the supply and return sides of said duct work.

6. In a space conditioning system. means for thermally treating a conditioning medium, said means comprising a medium heating portion and a medium cooling portion, means disposed to circulate said conditioning medium through said system, means responsive to a temperature indicative of outdoor temperature for causing said conditioning medium tobe directed to said heating or cooling portion of said system, means responsive to the temperature of the space being conditioned for controlling the flow of conditioning medium from said system, and means responsive to the flow of the conditioning medium for varying the temperature of the said medium.

7. In a space conditioning system, means for thermally treating a conditioning medium, said means comprising a medium heating portion and a medium cooling portion, means disposed to circulate said conditioning medium through said system, a timer, means responsive to the temperature in a selected location for actuating said timer to cause said conditioning medium to be alternately directed to said heating portion and said cooling portion of said system, means responsive to the temperature of the space being conditioned for controlling the flow of conditioning medium from said system, and means for circulating the conditioning medium within said system when said means responsive to space temperature curtail flow therefrom.

8. In a space conditioning system, means for thermally treating a conditioning medium, said means comprising a medium heating portion and a medium cooling portion, means disposed to circulate said conditioned medium through said system, means responsive to the temperature in a selected location for causing said conditioning medium to be directed to said heating portion or cooling portion of said system, and pressure actuated means for altering the extent of thermal treatment of said conditioning medium in accordance with the flow of said medium from said system.

9. In a space conditioning system, means for thermally treating a conditioning medium, said means comprising a medium heating portion and a medium cooling portion, means disposed to circulate said conditioned medium through said system, means responsive to the temperature in a selected location for causing said conditioning medium to be directed to said heating portion or cooling portion of said system, means responsive to the temperature of the space being conditionedfor controlling the flow of conditioned medium from said system, and pressure actuated means for altering the extent of thermal treatment of said conditioning medium in accordance with the flow of said medium from said system. I

10. In a control apparatus, means for preparing and controlling the delivery of a conditioning medium to a plurality of spaces to be conditioned and comprising, a heating unit, a cooling unit, said units being adjustable to various temperature operating ranges, a plurality of individually controlled outlets, means for circulating the conditioning medium through said units and said outlets, damper means for directing the flow of said conditioning medium through either of said units, condition responsive means for operating said damper means to prevent flow of said conditioning medium through either of said units, means for limiting the temperature operating ranges of said units, and pressure actuated means for resetting said limiting means in accordance with pressure within said control apparatus.

11. In a heating and cooling system for a plurality of spaces, means for selectively delivering heating or cooling medium to said spaces, means responsive to the temperature of the medium being delivered to the space and to the temperature of each space for determining the effect of said medium in each of said spaces, and means responsive to outdoor temperature in control of said selective delivery means.

12. In a heating and cooling system for a plurality of spaces, means for selectively delivering heating and cooling medium to said spaces, means responsive to the temperature of the medium being delivered to the spaces and to the temperature of each space for determining the efl'ect of said medium in each of said spaces, and time operated means for periodically operating said selective delivery means to alternately cause the delivery of heating and cooling medium to said spaces.

13. In a heating and cooling system for a plurality of spaces, an outlet in each space, means for selectively delivering hot or cold air to all of said outlets at the same time, thermostatic means associated with each outlet responsive to the temperature of the space and the temperature of the air being delivered to the outlet and operable to prevent the delivery of cold air when the space is cold and to prevent the delivery of hot air when the space is hot while permitting the delivery of cold air when the space is hot and permitting the delivery of hot air when the space is cold, and means responsive to outdoor temperature in control of said selective delivery means to cause delivery of hot air to said outlets when the outdoor temperature is low and the delivery of cold air to said outlets when the outdoor temperature is high.

14. In a heating and cooling system for a plurality of spaces, an outlet in each space, means for selectively delivering hot and cold air to all of said outlets at the same time, thermostatic means associated with each outlet responsive to the temperature of the space and the temperature of the air being delivered to the outlet and operable to prevent the delivery of cold air when the space is cold and to prevent the delivery. of hot air when the space is hot while permitting the delivery of cold air when the space is hot and permitting the delivery of hot air when the space is cold, and timing means in control of said selective delivery means for alternately causing hot and cold air to be delivered to said outlets.

15. In a heating and cooling system for a plurality of spaces, an outlet in each space, means for selectively delivering hot or cold air to all of said outlets at the same time, thermostatic means associated with each outlet responsive to the temperature of the space and the temperature of the air being delivered to the outlet and operable to prevent the delivery of cold air when the space is cold and to prevent the delivery of hot air when the space is hot while permitting the delivery of cold air when the space is hot and permitting the delivery of hot air when the space is cold, means responsive to outdoor temperature in control of said selective delivery means to cause delivery of hot air to said outlets when the outdoor temperature is low and the delivery of cold air to said outlets when the outdoor temperature is high, and timing means controlled by said outdoor temperature responsive means at intermediate outdoor temperature, said timing means actuating said selective delivery means to cause hot 16 and cold air to be alternately delivered to said outlets.

16. In combination, means for changing the temperature of a temperature changing fluid, means responsive to the temperature of the fluid in control of said temperature changing means, means for circulating the fluid, means for throttling the flow of said fluid whereby its pressure is increased, and means responsive to the pressure said conditioning means, means for circulating medium in condtion changing relation to said conditioning means, said circulating means discharging into a plenum chamber, and means responsive to the pressure in the said plenum chamber for adjusting said temperature responsive means.

18. In conditioning apparatus, in combination, a conditioning element, adjustable means for controlling said element, means for circulating fluid through said apparatus, said circulating means discharging into a plenum chamber and having an inlet portion, by-pass means between said plenum chamber and said inlet portion, movable means restricting air flow through said bypass means, and means connecting said movable means to said controlling means for adjusting the same in response to air flow through the said bypass means.

19. In an air conditioning apparatus, a temperature changing element, conduit means including an inlet portion and a discharge portion enclosing said temperature changing element, circulating means located between said inlet and discharge portions, by-pass means connecting said 'inlet and discharge portions, adjustable means responsive to temperature in the discharge portion of said conduit means, and means responsive to pressure in said discharge portion for adjusting said temperature responsive means.

20. In a forced air, temperature changing apparatus, in combination, a blower, a temperature changing element, conduit means including an inlet portion extending to said blower and a discharge portion extending from said blower and in heat exchange relation with said element, adjustable means responsive to temperature in said discharge portion for controlling said element, and means responsive to the diflerence in pressure between said discharge and inlet portions of said conduit means for adjusting said temperature responsive means.

21. Control apparatus for air conditioning apparatus comprising in combination, an adjustable temperatureresponsive limit controller, movable means responsive to the pressure of the air to which said controller responds, and means connecting said movable means to said controller in such manner that said controller may be adjusted to lower temperature values when the pressure to which said pressure responsive means responds is relatively high.

22. In a temperature changing apparatus, duct means having a plurality of individually controlled outlets connected thereto, mechanical means for circulating temperature changing medium through said duct means, temperature changing means for changing the temperature of the medium in said duct means, switching means for controlling said temperature changing means, movable means responsive to the air pressure in said duct means downstream from said circulating means, and means connecting said movable pressure responsive means in controlling ing means, and mechanical means responsive to the pressure o1'- said fluid downstream from said circulating means for adjusting said control device. I

24. In air conditioning apparatus, conduit means, flow control means for variably restrictin: air flow through said conduit means, heat exchange means located within said conduit means, adjustable means for controlling said heat exchange means, mechanical means for forcing air through said conduit means, and control apparatus including movable means responsive to air pressure in said conduit means downstream from said mechanical air forcing means connected in controlling relation to said adjustable means.

ALWIN B. NEWTON.

REFERENCES CITED The followingreferences are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,737,040 Buikeley et a1 Nov. 26, 1929 1,985,050 Merle Dec. 18, 1934 2,226,081 Stuart Dec. 24, 1940 2,284,764 Parks June 2, 1942 2,291,769 Smeilie Aug. 4, 1942 2,295,841 Hallinan Sept. 15, 1942 2,327,664 Otis Aug. 24, 1943 

